Borate esters prepared by successive reactions of boric acid with glycol monoethers and polyols

ABSTRACT

BORATE ESTERS OF THE FORMULA:   (R3-((O-CH2-CH(-R1))M-(O-CH2-CH(-R2))N-O)-B(-(O-(CH(-R2)-   CH2-O)N-(CH(-R1)-CH2-O)M)-R4)-O)P-R5   WHERE R1 AND R2 ARE BYDROGEN OR METHYL; R3 AND R4 ARE EACH AN INDEPENDENTLY SELECTED ALKYL GROUP HAVEING FROM 1 TO 20 CARBON ATOMS; R5 IS THE ORGANIC RESIDUE EXCLUSIVE OF REACTIVE HYDROXYL GOUPS OF A POLYOL, P IS AN INTEGER OF FROM 2 TO 6 INCLUSIVE AND N AND M ARE POSITIVE INTEGERS INDEPENDENTLY SELECTED IN EACH CHAIN AND WHOSE SUM IN EACH CHAIN IS FROM 2 TO 20, ARE PREPARED BY SUCCESSIVELY REACTING BORIC ACID WITH A GLYCOL MONOETHER AND A POLYOL. THESE ESTERS ARE USEFUL AS STABILIZERS AND CORROSION INHIBITORS FOR LUBRICANTS AND NON-AQUEOUS HYDRAULIC FLUIDS.

United States Patent Office 3,637,794 Patented Jan. 25, 1972 US. Cl. 260-462 7 Claims ABSTRACT OF THE DISCLOSURE Borate esters of the formula:

where R and R are hydrogen or methyl; R and R are each an independently selected alkyl group having from 1 to 20 carbon atoms; R is the organic residue exclusive of reactive hydroxyl groups of a polyol, p is an integer of from 2 to 6 inclusive and n and m are positive integers independently selected in each chain and whose sum in each chain is from 2 to 20, are prepared by successively reacting boric acid with a glycol monoether and a polyol. These esters are useful as stabilizers and corrosion inhibitors for lubricants and non-aqueous hydraulic fluids.

This invention relates to novel borate esters. In particular, this invention relates to novel borate esters of the general formula:

where R and R are independently selected from the group consisting of hydrogen or methyl; R and R are each an independently selected alkyl group having from 1 to 20 carbon atoms; R is the organic residue exclusive of reactive hydroxyl groups of a polyol, p is an integer of from 2 to 6 inclusive and n and m are positive integers independently selected in each chain and Whose sum in each chain is from 2 to 20.

The novel borate esters of this invention are useful as desiccants for drying of gases and as stabilizers and corrosion inhibitors for lubricants and non-aqueous hydraulic fluids, such as those based on glycols, polyglycols, the alkylene oxide adducts of phenols and the dialkyl ethers of glycols and polyglycols.

The novel esters of this invention are stable at elevated temperatures and they possess very high boiling points. On hydrolysis these novel borate esters yield ultimately the glycol monoether, boric acid and the polyol employed in preparing these compounds.

The novel borates of this invention are also useful as ingredients in soldering of brazing fluxes. They also find use as compounding ingredients for natural and synthetic resins, since in addition to serving as plasticizers, they reduce the flammability of the material being plasticized.

In general, the novel compounds of this invention are prepared in two steps. In the first step, a stoichiometric amount of a boron-containing compound, such as orthoboric acid, is reacted with a glycol monoether or mixture of glycol monoethers to yield an intermediate borate compound (A). Secondly, the intermediate borate compound is reacted with a polyol having from 2 to 6 inclusive hydroxyl groups to obtain the novel borate compounds (-13) of the present invention. The two reactions, namely the reaction of the first stage and the reaction of the second stage, proceed as shown in the following equations where for purposes of illustration a single glycol monoether is utilized in preparing compound (A):

I. 2 REOCH CHRQ -(OCH CHRQQOH H3803 R Eoca casg (ocu ci-mp g B OR (A) i R @ca cuap (ocn caw dl 2a,,o II- R 533011 01112 (OCI-IZCHRZ)\ E\\ B- on" 11 mm P P R Foca caxp (ocn cmm q wherein R R R n, m and p have the same meaning as previously described and R is alkyl of from 1 to 20 carbon atoms.

In the preferred method of preparation boric acid is employed as the boron-containing material and an inert water-azeotroping solvent is added to the reaction vessel along with the glycol monoether starting material. The water-azeotroping solvent is selected so that the azeotrope distils at a temperature below the boiling point of the monohydroxy compound. The temperature of the reaction mixture is initially maintained preferably between 0 and 200 C. and desirably at the distillation temperature of the water-solvent azeotrope. The use of a graduated Barrett receiver facilitates the measurement and separation of the water of condensation. Preferably, the reaction is conducted Without an added catalyst to simplify the utilization of the product, although an esterification catalyst may be employed, if desired. When the water removed is equivalent to the stoichiometric requirement to yield the intermediate borate compound (A), the reaction mixture is cooled to a temperature below its reflux temperature and a stoichiometric amount of a polyol bridging compound is introduced into the reaction mixture. After stirring the mixture to ensure uniformity, it is again heated so that azeotropic removal of Water is resumed. As soon as the removal of water is essentially completed, the solvent is then conveniently removed by distillation. The borate ester remaining after removal of the solvent can be further stripped under reduced pressure to remove any unreacted starting materials present. Other methods are known in the art for purifying the borate ester. For example, the ester can be recovered as the pure product by extraction with a suitable solvent followed by evaporation of the solvent.

Boron compounds which are suitable as starting materials for the preparation of the novel boron esters include orthoboric acid, metaboric acid, boric oxide, and the like. Orthoboric acid, metaboric acid and boric oxide are preferred because of their relatively low cost. Toluene and benzene are the preferred azeotrope-forming solvents; however, other inert solvents may be utilized providing that they form azeotropes with water, such as, for example, xylene, ethylbenzene, mesitylene and the like.

Glycol monoethers suitable for use in the preparation of the novel borate esters of this invention include those of the formula:

R (OCH CHR --(OCH CHR OH where R and R are independently selected from the group consisting of hydrogen and methyl, R is an alkyl group containing from 1 to 20 carbon atoms, and m and n are positive integers whose sum is from 2 to 20.

Many glycol monoethers are commercially available. Suitable glycol monoethers, for example, include:

(1) CH (OCH CH OH (3) CH (OCH CH OH (4) CH (OCH CHCH 3 OCH CH OH 5 CH (OCH CH (OCH CHCH )OH (6) CH (OCH CH (OCH CHCH GH (7) CH (OCHCH (OCH CHCH H (8) CH (OCH CHCH 0H (9) CH (OCH CHCH OH (12) C H (OCH CH OH (16) C H OCH CH 0H (21) C H OCH CH (OCH CHCH OH 21( 2 2)14 (23) C H (OCH CHCH (OCH2CH2) OH (24) C H (OCH CHCH OH (25) C H (OCH CHCH (OCH CHCH 0H (26) C H (OCH CHCH OH Mixtures of the above-listed glycol monoethers can also be used.

Polyols suitable for use in connecting two or more of the intermediate borates of the formula:

Ba[(0CH CHR (OCH CHRQHO] B-OH R4[(OCH2CHR1)m (0CH2OHR2)11O] wherein R R R R m and n have the same meaning as previously described, include compounds of the formula:

wherein p is an integer of from 2 to 6 inclusive and wherein R is the organic residue exclusive of the reactive hydroxyl groups. Useful polyols include (1) glycols of the formula:

wherein R is alkylene of from 2 to 10 carbon atoms and r is an integer of from 1 to 10; (2) thioglycols selected from the group consisting of thiodiethylene glycol and thiodipropylene glycol; (3) amines of the formula:

wherein s is an integer of from 2 to 3 inclusive, 2 is an integer of from 1 to 10 inclusive, R is selected from the group consisting of hydrogen and methyl and R is selected from the group consisting of hydrogen and alkyl of from 1 to 4 carbon atoms and 4) polyols such as polyhydroxy substituted alkanes having from 3 to 6 inclusive hydroxyl groups.

Specific examples of the above-mentioned polyols include for example, ethylene glycol, propylene glycol, butylene glycol, isobutylene glycol, pentanediol, hexylene glycol, neopentyl glycol, diethylene glycol, tetraethylene glycol, hexaethylene glycol, decaethylene glycol, dipropylene glycol, triisopropylene glycol, tetrapropylene glycol, hexabutylene glycol, 2-ethyl-l, 3-hexanedi0l, thiodiethylene glycol, thiotripropylene glycol, diethanol- 4 amine, dipropanolamine, triethanolamine, tributanolamine, methyl diethanolamine, ethyl diethanolamine, methyl dipropanolamine, ethyl dipropanolamine, methyl dibutanolamine, propyl dipropanolamine, butyl diethanolamine, glycerol, trimethylol propane, pentaerythritol, sorbitol, mannitol and 1,2,6-hexanetriol.

The novel borate esters of this invention can be utilized to prepare brake fluid having boiling points in excess of 490 F. In such brake fluid compositions these borates form the major component and are present in amounts of from about 55 to about percent by weight of the final fluid. A typical hydraulic fluid composition utilizing the product of Example V, which has the formula:

is given below:

Percent by weight Product of Example V 75.0 Triethylene glycol monomethyl ether 7.5 Diethanolamine 2.0 Polyethylene glycol (mol. wt. 200) 15.0 Sodium nitrite 0.05

This formulation was tested in accordance with the appropriate methods of the SAE I700 for hydraulic brake fluids and the following properties were observed:

Reflux boiling point: 509 F.

Viscosity at:

212 F.: 2.7 cs. 40 F.: 3380 cs. Cold test:

6 days at 40 F.: clear liquid. 6 hours at 58 F. clear liquid. Rubber swelling:

(Natural rubber hours 158 F.: 2.5 percent diameter.

(Styrene-butadiene, 70 hours, 248 F.): 4.2 percent diameter.

Water tolerance (3.5 percent vol., added water):

24 hours at 40 F. clear liquid. 24 hours at F. clear liquid.

These values illustrate the highly superior properties of hydraulic fluids prepared with the novel borates of this invention. The addition of 3.5 percent volume of water to the above formulation yielded a fluid having a reflux boiling point of 368 F. according to the procedure of ASTM 1120-65, whereas typical currently commercial brake fluids with 3.5 percent added water have inferior (i.e., below 302 F. when tested in the same manner.

The following examples illustrate specific embodiments of this invention and are to be considered not limitative:

EXAMPLE I A total of 985 g. (6 moles) of CH (OCH CH OH, 185.5 g. (3 moles) of orthoboric acid and 510 ml. of toluene were mixed together in a 2 liter, round-bottom, 3-neck flask equipped with a magnetic stirrer. With heating at reflux temperature and stirring, the water of condensation was removed as formed by azeoptropic action. When 108 ml. (6 moles) of water had separated, the reaction mixture was allowed to cool below reflux temperature. Then 179 g. (1.5 moles) of 2-methyl-2,4-pentanediol was introduced and the reaction mixture was stirred and reheated to reflux temperature in order to resume azeotroping out the water of condensation. As soon as the water had been essentially all removed, the toluene was distilled oil and the residue containing the product was stripped under water aspirator vacuum at 90 to 120 C. pot temperature for 1.5 hours-in order to remove CH3) CHgCHghO unreacted products. A total of 1192 g. of product (essentially 100 percent of theory), a clear colorless liquid with a viscosity at 40 C. of approximately 1400 es. and having the formula:

Analysis.-Calculated (percent): B, 2.82. Found (percent): B, 2.78.

EXAMPLE H In a manner similar to that in Example I, 242.7 g. (2 moles) of CH (OCH CH OH, 61.85 g. (1 mole) orthoboric acid and 230 ml. toluene were mixed together and heated at reflux temperature until 36 ml. (2 moles) of water had been removed as the azeotrope. The reaction mixture was allowed to cool below reflux temperature and 53.6 g. (0.5 mole) of diethylene glycol was introduced, with continued stirring. The mixture was reheated to resume azeotroping action. When water separation essentially had ceased, the toluene was distilled off and the residue was stripped under full water aspirator vacuum at a pot temperature of 138 to 140 C. for minutes to remove unreacted starting materials. Product in the amount of 291 g. (95 percent of the theoretical yield), a clear, light straw-colored liquid, was obtained. This product, Which has the formula:

exhibited a viscosity at -40 C. of 3632 cs.

Analysis.Calculated (percent): C, 47.86; H, 8.70;

B, 3.59. Found (percent): C, 46.76, 46.49; 8.46, 8.70;

EXAMPLE III In a manner similar to Example I, 324 g. (2 moles) of CH (OCH CH OH, 61.8 g. (1 mole) of orthoboric acid and 265 ml. of toluene were mixed together and heated until a total of 36 ml. (2 moles) of water had been removed as the azeotrope. 45.4 g. (0.33 mole) of commercial trimethylol propane was introduced into the hot liquid. As soon as the solid trimethylol propane flakes had dissolved in the stirred reaction mixture,

azeotropic removal of water was resumed. When separation of water had essentially ceased, the toluene was distilled off and the residue was stripped at 140 to 148 C. pot temperature under full water aspirator vacuum for approximately 10 minutes. A total of 375.4 g. (99.5

6 percent of theoretical yield) of a clear, colorless liquid having the formula:

0 (CH CH2O) CH CH2O-B OH2Q-B O(CH2CH20)3CH3 was obtained. The product exhibited a viscosity at 40 C. of 6161 cs.

Analysis.-Calculated (percent): B, 2.88. Found (percent): B, 2.87.

EXAMPLE IV In a manner similar to the preceding examples, 324 g. (2 moles) of CH (OCH CH OH, 61.8 g. (1 mole) of boric acid and 275 ml. of toluene were mixed together and heated with continuous stirring until 36 ml. of water had been removed as the azeotrope. Then 30.4 g. (0.17 mole) of sorbitol was introduced and azeotroping was continued until separation of water had essentially ceased. After the toluene had been distilled oil, the residue was stripped under full water aspirator vacuum at a pot temperature of to C. for approximately 10 minutes to remove unreacted starting materials. A total of 360 g.

of product (97 percent of theory), a clear, colorless liquid, having the formula:

7 was obtained. The Viscosity of the product at 40 C. EXAMPLE VH was 11,827 cs. Exam 1 I p e was repeated using a lower homolog, spe Analysls-calculated (perceno- Fund (Per' cifically CH (OCH CH OH, with the same molar ratios cent): of other reactants, to yield a clear colorless liquid prod- EXAMPLE v not (97 percent of theory) having the following formula: In a manner similar to Example I, 641.3 g. of commercial (99 percent) CH (OCH CH OH, 164.9 g. ortho- "2" 2 2 2 "a boric acid and 200 m1. of toluene were mixed together and heated. Simultaneously, the water of condensation formed was removed overhead as the water-toluene azetrope. After essentially 5.33 moles of water had been removed, the reaction mixture was allowed to cool below reflux CHTC'CH2'CH'CH3 temperature following which 82.7 g. of 99 percent glycer- CH3 ine was added. Azeotropic removal of water was resumed.

As soon as the water separation had essentially ceased, The vlscoslty of ther Pmduct at mmus Q was P- ci tocu cag o o (CH2CH2O)2CH3 the toluene was removed by distillation and the remainy 450 ing reaction mixture stripped under full aspirator vacuum Analysis-Calculated (P Found (P at a pot temperature of 145 to 150 C. for 15 minutes to cent)! remove unreacted starting materials. Borate ester in the EXAMPLE VIII amount of 734 Percent of the theoretical Y In a manner similar to preceding examples, 324 g. (2 a clear, light straw-colored liquid, having the formula: moles) f C AO CH 13 1 mole) Orthoboric acid and 250 ml. of toluene were mixed together /O(CH2CH2O)2CH3 and heated with continuous stirring until 36.5 ml. of CH 2 water was removed as the azeotrope. Then 34.4 g. (0.25 2 mole) of pentaerythritol was introduced and stirred until MCHZCHZWZCHS it dissolved. Azeotropic removal of water was continued and an additional 17 ml. of water was removed and -0 (CH CH O) CH recovered. The mixture was then stripped under full water I aspirator vacuum while heating to 154 C. pot temper- Cl-lO-B ature to remove the toluene and any unreacted starting materials. A total of 364.5 g. of product (99.5 percent of z hz z theoretical) an essentially clear colorless liquid with a O z z z viscoslty at 40 C. of 9117 cs., having the formula: 5 ()(CH2OH20)3CH! CHZO'B 0-13 0(CH cH o) cH l owmomoncm CHs(OCzHz)sO IE: 0 (CHzCHzOhCH: was obtained. 40

Analysis-Calculated (percent): B, 3.88. Found (per- 0 CH2 to B t): B, 4 1'7 CH3(OC2H2):O H1 O(CHzCHzO)3CH EXAMPLE VI CH:(O C2H2)a0\ In a manner similar to Example III, a lower homolog, B-O specifically CH [OCH CH OH was substituted, using CHt(OCtH2)tO the same molar ratios of other reactants as were used in Example III, to yield a clear, light-colored product (96 Percent of theoretical) having a formula: fig f g 'gg (Patent) Found (P6P o (ctt cinonctr, EXAMPLE IX In a manner similar to the preceding examples, 242.7 g. (2 moles) of commercial CH (OCH CH OH, 61.84 (,(cgzcflzmzcga g. (1 mole) boric acid and 220 ml. toluene were mixed together and heated with continuous stirring until 36 ml. of water had been removed as the azeotrope. Then 61.9 g. (0.5 mole) of commercial thiodiethylene glycol was introduced. Azeotropic removal of water was continued O(GHzCH2o)2CH until separation of water had essentially ceased. After stripping the product under full water aspirator vacuum to a pot temperature of 159 C., to remove toluene and unreacted volatile materials, 298.5 g. (96.8 percent of theoretical) of clear yellow-brown liquid product was 0(CH CH O) CH obtained. The product which exhibited a viscosity at 40 C. of 5200 cs., has the formula:

was obtained.

0(Cli Cli 0) CH 6 ctr o s The product was fluid at 40 C.; viscosity at -40 C.=2627 cs. Analysis-Calculated (percent): C, 46.62; H, 8.48; Analysis.Calculated (percent): B, 3.57. Found (per- B, 3.50; S, 5.19. Found (percent): C, 45.97, 46.06; H, cent): B, 3.87. 8.17, 8.36; B, 3.36; S, 5.19, 5.31.

9 10 EXAMPLE X The product was a clear liquid at -40 C.

In a manner Similar to Example IX, 2 moles of AnalysiS.--Calculated (percent): B, 2.98. Found ,(per- CH (OCH CH OH, 1 mole of orthoboric acid and 220 13,310- ml. of toluene were mixed together and heated with EXAMPLE XIII stirring until 36 ml. of water had been separated. Next 5 54.65 g. (0.5 mole) of diethanolamine was introduced A sample of commercial butoxy ethoxy propanol was and azeotropic removal of water was continued overdistilled, discarding approximately percent forecut and night. The reaction mixture was stripped under full water approximately percent tail cut. 177 g. (1 mole) of the aspirator vacuum, with stirring and heating to a pot temmain (center) cut of colorless butoxy ethoxy propanol, perature of 143 C. to remove all toluene and unreacted 10 30.9 g. (0.5 mole) of boric acid and 200 ml. of toluene volatile starting materials. The resultant product, which were mixed and heated together, in a manner similar to weighed 281 g. (93 percent of theoretical), was a clear, the preceding examples, to remove 18 ml. (1 mole) of light-brown liquid with a viscosity at 40 C. of apwater. Then g. (0.25 mole) of 2-methyl-2,4-pentanediol proximately 15,500 cs. and having the following formula: Was introduced and azeotropic removal of water was CH3 OOH1CH2)2O 0(CH2CH20)2CH3 /B-OCHzCH21TICHzCHgO-B\ CH;\(0CH2CHz)z0 H 0(OHzCHgOhCH Analysis.-Calculated (percent): C, 47.9; H, 8.87; B, 3.60; N, 2.33. Found (percent): C, 46.92, 46.96; H, 8.77, 20 resumed and continued essentially to cessation. The prod- B, N 255 2 5 uct was then stripped to a pot temperature at 172 C.

EXAMPLE XI under full water aspirator vacuum to yield 208.3 g. (97

percent theory) of a clear, colorless liquid product hav- In a manner similar to Example IX, 2 moles of ing the formula:

4 i( H2 2 2 H Ha) 0\ /O(CH;CHCHZOCH2CH2O)C4HQ l 4 9(OCH2CH2OCH2CHCHs)O ll O(CH3CHCH2OCH2CH20)C4H9 I CHaCCH2CH-CH3 CH3 CH (OCH CH 01-1, 1 mole of orthoboric acid and 220 At C. the product was a clear liquid. mL toluene were m1xed together and heated with stirrlng 3r Analysis-Calculated (percent): B, 2.50. Found (pay. until 36 ml. of water had been separated. Next 61.77 g. 0 e t); B, 2 61 (0.5 mole) of methyl diethanolamine was introducedand EXAMPLE XIV azeotropic removal of water was continued overnight. The reaction mixture was then stripped under full water A mlxture of'homologous Polyethylem glycol mono aspirator vacuum, with stirring and heating to a pot temmethyl with an f molecular wmght of 186 peratureof 140 C. There was obtained 301 g. of product 40 (calculated from determmefi 3f Y of (98 percent of theoretical), a clear, brown li id i was employedas areactant 1n this experiment. The lowest a viscosity at C. f 1783 and having the {on molecular weight component of this mixture was trimula:

CH3(OCHZCH2)2O owmcmoncn,

B-OCHaCHz-N-CHzCHzO-B CH3(OCH;CH2)2O Ha O(CHzCHgO) CH AnalySl'S-Ca1u1ated (p fl C, 5O ethylene glycol monomethyl ether and the average formu- -B, 3.52; N, 2.28. Found (percent): C, 47.04, 46.71; H, 1 f th mixture EXAMPLE XII CH3(()CH2CH2)35QH A total of 592 g. (4 moles) of CHAOCHCHBCHQZOH 784 g. (4 mole s) of this mixture and 123.7 g. (2 moles) 1 3.7 g. moles) of orthoboric acid and 325 m1. toluene of USP boric acid were reacted in toluene, 1n the number of previous examples until 72 ml. (4 moles) of water were mixed and heated to ether while simultaneousl 72 ml. of water was removed as the azeotrope. Then 1%82 had been removed as azeotrope' Then 119 l (1 mole) g mole) of zmethylaampentanediol was introduced of hexylene glycol was introduced and azeotropic removal and the azeotropic removal of water was continued overggg i t resuned and continued, essentially to cessanight, at which time the separation of water essentially i nppmg ergacuum to 163 pot temperature had ceased. The reaction mixture was stripped under full m e manner 0 er examples fielded 914 (99's Wat aspirator vacuum While heating to a pot temp? percent of theoretical) of a clear, light-yellow product ature of 140 C. to remove the toluene and any unreacted havmg the formula: volatile starting materials. Product was recovered in the amount of 704 g. (97 percent of theoretical), a clear, yellow liquid having the formula:

/ CH 0 OH H 0 CH l owmorromonom s 1 P 3 CH3- -CHz-CH-CH3 H3 At 40 C. the product was a clear liquid.

1 1 Analysis-Calculated (percent): C, 52.0; H, 8.19; B, 2.36. Found (percent): C, 51.45, 51.78; H, 8.96, 9.09; B, 2.39.

EXAMPLE XV In a manner similar to the preceding examples, 324 g. (2 moles) of CH (OCH CH H, 61.8 g. (1 mole) of orthoboric acid and 250 ml. of toluene were mixed and heated together until 36 ml. (2 moles) of water was 12 Analysis-Calculated ,(percent): B, 1.10. Found (percent): B, 1.11.

Many other brake fluid compositions which utilize the novel borate esters of this invention are described in Arthur W. Sawyer and David A. Csejka application for Water-Insensitive Hydraulic Fluids Containing Bis-Borate Esters or Bridged-Borate Esters, application Ser. No. 653,- 335, filed July 14, 1967, now abandoned, which application is incorporated in its entiret herein.

separated as the azeotrope. A total of 54.2 g. (0.5 mole) What is claimed is: of 2,2-dimethyl-1,3-propanediol was then introduced. 1. A borate ester of the formula: Azeotropic removal of water was resumed and continued a[( G z R1)m(0 CHQCHRQUO] until water removal essentially ceased. The product was 1 stripped to a pot temperature of 165 C. under vacuum J as in the previous examples. Product in the amount of R4K0CH2CHR1 HF CH2CHRZ)-=O1 374 g. (97 percent of theoretical), a clear colorless liquid where R and R are independently selected from the product having a viscosity of 1605 cs. at 40 C. and group consisting of hydrogen and methyl; R and R are having the formula: each an independently selected alkyl group having from crmocmcumo ()(CHICHZO)3CHZ B-omuowm).01no-u (3113(0 omoumo ownzcrnonon,

was recovered. 1 to 20 carbon atoms; R is the organic residue exclusive of reactive hydroxyl groups of a polyol selected from the Analyszs.-Calculated (percent). B, 2.79. Found (per group consisting of: cent): B, 2.82. (1) glycols of the formula:

EXAMPLE XVI H Commercial isodecanol was oxypropylated by convenh 1k 1 f f 0 b w erein R is a y ene 0 rom 2 to 1 car on atoms tional techniques by charging isodecanol and an alkaline and ris an integer of from 140; and catalyst to a pressure reactor and then introducing propyl- (2) polyhydroxy substituted alkanes having from 3 to 6 inclusive hydroxyl groups ene oxide under cond1t1ons whlch yielded a clear colorless p is an integer of from 2 to 6 inclusive and n and m q This OXypropylated P Was found to have a are positive integers whose sum is from 2 to 20. hydroxyl number of 123, a calculated average molecular A bomte ester of clalm 1 havmg the formula: weight of 456 and the average formula to be: CH3) CHECHZMO /O(CH2OH2O)aCH3 13-0 0-13 1o 21( 2 a)a.1 l l crmocmcfimo ownzomo crn In a manner similar to previous examples, 456 g. (1

mole) of above oxypropylated product, 30.9 g. (0.5 mole) of orthoboric acid and 200 ml. of toluene were mixed and heated together until 18 ml. (1 mole) of water had been recovered as the azeotrope. 29.6 g. (0.25 mole) of 2-methyl-2,4-pentanediol was then introduced. Azeotroping was resumed and continued overnight at which time water separation had essentially ceased. The product was stripped to a pot temperature of 138 C. under vacuum as in previous examples. A total of 490 g. of a colorless, liquid product (essentially 100 percent of theory), a clear, viscous liquid at -40 C., having the formula:

was obtained.

3. The borate ester of claim 1 having the formula:

0113(0 (1112011930 ()(CHzCHzOhCHg B-OClizC(CHa)2C1IzO-B CH3(OCH2CH2);O O(CHzCHzO) CH 4. The borate ester of claim 1 having the formula:

O(CHzCH20)aCH3 CHzO--B O(CHzCH2O)aCH C(CHzCHzOhCH;

CH3O1'I2-CCH20B owmomouom O(CH2CHZO) OH: CHzO-B O(CH2CH20)3CH3 O( a 1)e.rCioHz1 2 3? UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5, 57,79 7 Dated January 5, 97

Inventor(s Arthur W. Sawyer and David A. Csejka It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 6, that portion of the formula reading "()(CH CHO OH3" should read --O(CH CH O) CH Column 5, line 10, that portion of the formula reading "CH -C-CH -CH-CH should read --CH -C-CH2-CH-CH Column 5, line 16, "B, 2.82. should read --B, 2.72.

Column 10, line 28, that portion of the formula-reading "CH -C-CH2-CH-CH should read --CH -C'3-CH2-CH-CH Column 1 claim 6, those portions of the formula reading "O(CH2CH2O)3CH3 should read --O(CH2CH2O)2CH3-- Signed and sealed this 2nd day of January 1973.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 32 3? UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION- Patent No. 3, 57,794 Dated January 25, 1972 Inventofls Arthur w. Sawyer and David A. Cse'jka It is certified that error appears inthe above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 6, that portion of the formula reading "O(CH CHO OH should read --O(CH CH O) CH Column 5, line 10, that portion of the formula reading "CH .-C-CH -CH-CH should read --CH -+C-CH -CH-CH Column 5, line 16, "B, 2.82. should read --B, 2.72.

Column 10, line 28, that portion of the formula reading "CH -C-CH -CH-CH should read --CH -C-CH -CH-CH Column 1 claim 6, those portions of the formula reading "O(CH CH O) CH should read --O(CH CH2O) CH Signed and sealed this 2nd day of January 1973.

(SEAL) Attest:

EDWARD M. PLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

